Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Modeling Inequality and Mobility with Stochastic Processes

Fischer, Thomas LU (2017) p.1-55
Abstract
This paper presents tractable two parameter stochastic processes of the drift-diffusion class in order to model economic processes with a focus on income. Starting from the resulting closed-form, cross-sectional distributions, easy-to-interpret expressions for mobility and inequality (including the popular Gini-coefficient) are derived. The general processes are applied to discuss income mobility and inequality and fitted to US evidence. Heteroscedasticity is crucial to explaining skewed distributions of log-income, while multiplicative risk is necessary for generating Pareto tails. Furthermore, introducing Poisson death jumps also generates Pareto tails in the low end of the distribution and therefore fits the evidence best. Finally, we... (More)
This paper presents tractable two parameter stochastic processes of the drift-diffusion class in order to model economic processes with a focus on income. Starting from the resulting closed-form, cross-sectional distributions, easy-to-interpret expressions for mobility and inequality (including the popular Gini-coefficient) are derived. The general processes are applied to discuss income mobility and inequality and fitted to US evidence. Heteroscedasticity is crucial to explaining skewed distributions of log-income, while multiplicative risk is necessary for generating Pareto tails. Furthermore, introducing Poisson death jumps also generates Pareto tails in the low end of the distribution and therefore fits the evidence best. Finally, we develop a micro-founded model for income inequality that fits the current US evidence and permits discussing the welfare effects of tax reforms given that individuals also adjust their labor supply and human capital accumulation. According to the model current US taxation is close to its welfare optimum. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Working paper/Preprint
publication status
published
subject
keywords
income and wealth inequality, mobility, drift-diffusion process, stationary distribution, fat tails, D3, C46, C32
pages
1 - 55
publisher
SSRN
DOI
10.2139/ssrn.3090904
language
English
LU publication?
yes
id
2bc259dd-56ec-490f-bbe0-ad3fc03e0533
date added to LUP
2025-02-28 15:55:47
date last changed
2025-04-04 14:50:12
@misc{2bc259dd-56ec-490f-bbe0-ad3fc03e0533,
  abstract     = {{This paper presents tractable two parameter stochastic processes of the drift-diffusion class in order to model economic processes with a focus on income. Starting from the resulting closed-form, cross-sectional distributions, easy-to-interpret expressions for mobility and inequality (including the popular Gini-coefficient) are derived. The general processes are applied to discuss income mobility and inequality and fitted to US evidence. Heteroscedasticity is crucial to explaining skewed distributions of log-income, while multiplicative risk is necessary for generating Pareto tails. Furthermore, introducing Poisson death jumps also generates Pareto tails in the low end of the distribution and therefore fits the evidence best. Finally, we develop a micro-founded model for income inequality that fits the current US evidence and permits discussing the welfare effects of tax reforms given that individuals also adjust their labor supply and human capital accumulation. According to the model current US taxation is close to its welfare optimum.}},
  author       = {{Fischer, Thomas}},
  keywords     = {{income and wealth inequality; mobility, drift-diffusion process; stationary distribution; fat tails; D3; C46; C32}},
  language     = {{eng}},
  note         = {{Working Paper}},
  pages        = {{1--55}},
  publisher    = {{SSRN}},
  title        = {{Modeling Inequality and Mobility with Stochastic Processes}},
  url          = {{http://dx.doi.org/10.2139/ssrn.3090904}},
  doi          = {{10.2139/ssrn.3090904}},
  year         = {{2017}},
}